This invention relates to a method and apparatus for improving and protecting the health and alertness, particularly cardiovascular and mental functions, of individuals who are engaged in reduced physical activity, particularly when seated. More particularly, the invention is directed to sensing the drowsiness of such individuals by sensing a parameter of the individual's body that, at known values of the parameter, indicates a drowsiness condition and then applying stimulations to the body of such individuals to counteract the drowsiness, particularly by reversing the pooling of blood in the lower extremities of the individual's body. The applied stimulations are in the form of a wave applied to the body of the individual. The wave progresses from a more inferior location on the individual toward a more superior position. The crests of the wave cause a compression or contraction of the individual's muscles which pushes blood from the lower extremities into the upper body.
When a person remains in a seated posture for a period of time, the person's venous blood shifts disproportionately away from the brain and into the lower extremities. This pooling of the blood in the legs results in a reduced blood flow to the brain which, in turn, causes drowsiness and reduced attentiveness. When a person is engaged in normal physical activity, such as walking or other physical exercise, the normal periodic contraction of the leg and other muscles assists in pumping the blood upwardly in the body away from the lower extremities. However, when a person is seated, the person is engaged in reduced muscle activity so the muscles, especially those in the lower extremities, are less often or never contracted. Consequently, while gravity continues to attract blood downward into the lower extremities, the muscles are not assisting in moving the blood upward in the body.
There are several undesirable consequences of this pooling of the blood in the lower extremities. One consequence is that a person driving an automobile or other vehicle or operating other machinery becomes drowsy, inattentive and less vigilant. All of these consequences have an obvious undesirable effect upon the person's ability to operate a vehicle or machinery in a safe manner. Unfortunately this problem sometimes leads to increased operator error, not only for persons operating machinery, but also for others such as persons sitting at and operating a computer or a student taking a test in school.
There are also additional long term health consequences that result from excessive occurrences and lengthy time intervals of such blood pooling.
For example, blood pooling in the lower extremities contributes significantly to sleep apnea because the blood pooling causes retained fluid. The sleep apnea itself contributes to further drowsiness and inattentiveness because it results in less effective rest. The retained fluid results in an exponential decrease of airflow with resultant disturbed sleep, increased risk of obstructive sleep apnea and cardiovascular sequelae. The disturbed sleep results in drowsy driving, operator error and an increased risk of vehicular accidents. Disrupted sleep can also lead to some form of Attention Deficit Disorder. A method and apparatus that would reduce the pooling of blood in the lower extremities, of for example a truck driver, would not only improve attentiveness by reducing drowsiness and increasing attentiveness during operation of the truck, but would also improve the quality of rest and the improved alertness gained from the better rest.
Another health consequence example is that blood pooling as a result of physical inactivity can contribute significantly to the development of varicose veins. Prolonged inactivity from sitting causes blood pressure to rise in the veins of the lower extremities. If the pressure rises above the structural limits of the veins, a likelihood that increases with age, the increased pressure causes stretching of the vessel walls (varicose veins). Simultaneously, fluid is expressed through the venous walls into the soft tissue of the legs resulting in fluid retention and edema
It is therefore an object and feature of the invention to provide an apparatus and method for reducing the blood pooling while a person is seated and relatively inactive and thereby reducing the undesirable health and safety problems that blood pooling can cause. The invention is applicable to persons confined in a wheelchair, truck and motor vehicle drivers and occupants, aircraft pilots and occupants, heavy equipment operators, bedridden individuals, computer operators and students of all ages.